Training laboratories have become too far advanced in empirical activities and lagged behind in theoretical examinations. This paper is designed to identify its problem areas, while reviewing its present status in Japan. The following six problems will be addressed in the process. 1) The effects produced through the first experience with training laboratories, 2) the effects of the participants' cognition that they are allowed to participate in training laboratories as a special favor are not definitely distinguished from the overall effects of training laboratories. 3) The effects of techniques and tools employed for training laboratories are not fully analyzed. 4) There are few studies in which control groups are used. 5) Laboratory experiments are not conducted as often as they should be. 6) Most of these studies are not carried out by integrating those already existing group interaction theories.